tools/perf/util/help-unknown-cmd.c

   1 #include "cache.h"
   2 #include "config.h"
   3 #include <poll.h>
   4 #include <stdio.h>
   5 #include <subcmd/help.h>
   6 #include "../builtin.h"
   7 #include "levenshtein.h"
   8
   9 static int autocorrect;
  10
  11 static int perf_unknown_cmd_config(const char *var, const char *value,
  12                                    void *cb __maybe_unused)
  13 {
  14         if (!strcmp(var, "help.autocorrect"))
  15                 return perf_config_int(&autocorrect, var,value);
  16
  17         return 0;
  18 }
  19
  20 static int levenshtein_compare(const void *p1, const void *p2)
  21 {
  22         const struct cmdname *const *c1 = p1, *const *c2 = p2;
  23         const char *s1 = (*c1)->name, *s2 = (*c2)->name;
  24         int l1 = (*c1)->len;
  25         int l2 = (*c2)->len;
  26         return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
  27 }
  28
  29 static int add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
  30 {
  31         unsigned int i, nr = cmds->cnt + old->cnt;
  32         void *tmp;
  33
  34         if (nr > cmds->alloc) {
  35                 /* Choose bigger one to alloc */
  36                 if (alloc_nr(cmds->alloc) < nr)
  37                         cmds->alloc = nr;
  38                 else
  39                         cmds->alloc = alloc_nr(cmds->alloc);
  40                 tmp = realloc(cmds->names, cmds->alloc * sizeof(*cmds->names));
  41                 if (!tmp)
  42                         return -1;
  43                 cmds->names = tmp;
  44         }
  45         for (i = 0; i < old->cnt; i++)
  46                 cmds->names[cmds->cnt++] = old->names[i];
  47         zfree(&old->names);
  48         old->cnt = 0;
  49         return 0;
  50 }
  51
  52 const char *help_unknown_cmd(const char *cmd)
  53 {
  54         unsigned int i, n = 0, best_similarity = 0;
  55         struct cmdnames main_cmds, other_cmds;
  56
  57         memset(&main_cmds, 0, sizeof(main_cmds));
  58         memset(&other_cmds, 0, sizeof(main_cmds));
  59
  60         perf_config(perf_unknown_cmd_config, NULL);
  61
  62         load_command_list("perf-", &main_cmds, &other_cmds);
  63
  64         if (add_cmd_list(&main_cmds, &other_cmds) < 0) {
  65                 fprintf(stderr, "ERROR: Failed to allocate command list for unknown command.\n");
  66                 goto end;
  67         }
  68         qsort(main_cmds.names, main_cmds.cnt,
  69               sizeof(main_cmds.names), cmdname_compare);
  70         uniq(&main_cmds);
  71
  72         if (main_cmds.cnt) {
  73                 /* This reuses cmdname->len for similarity index */
  74                 for (i = 0; i < main_cmds.cnt; ++i)
  75                         main_cmds.names[i]->len =
  76                                 levenshtein(cmd, main_cmds.names[i]->name, 0, 2, 1, 4);
  77
  78                 qsort(main_cmds.names, main_cmds.cnt,
  79                       sizeof(*main_cmds.names), levenshtein_compare);
  80
  81                 best_similarity = main_cmds.names[0]->len;
  82                 n = 1;
  83                 while (n < main_cmds.cnt && best_similarity == main_cmds.names[n]->len)
  84                         ++n;
  85         }
  86
  87         if (autocorrect && n == 1) {
  88                 const char *assumed = main_cmds.names[0]->name;
  89
  90                 main_cmds.names[0] = NULL;
  91                 clean_cmdnames(&main_cmds);
  92                 fprintf(stderr, "WARNING: You called a perf program named '%s', "
  93                         "which does not exist.\n"
  94                         "Continuing under the assumption that you meant '%s'\n",
  95                         cmd, assumed);
  96                 if (autocorrect > 0) {
  97                         fprintf(stderr, "in %0.1f seconds automatically...\n",
  98                                 (float)autocorrect/10.0);
  99                         poll(NULL, 0, autocorrect * 100);
 100                 }
 101                 return assumed;
 102         }
 103
 104         fprintf(stderr, "perf: '%s' is not a perf-command. See 'perf --help'.\n", cmd);
 105
 106         if (main_cmds.cnt && best_similarity < 6) {
 107                 fprintf(stderr, "\nDid you mean %s?\n",
 108                         n < 2 ? "this": "one of these");
 109
 110                 for (i = 0; i < n; i++)
 111                         fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
 112         }
 113 end:
 114         exit(1);
 115 }